Throughout
Spanish America and the
Spanish East Indies, the plaza mayor of each center of administration held three closely related institutions: the
cathedral, the cantabile or administrative center, which might be incorporated in a wing of a governor's
palace, and the audience or law court. The plaza might be large enough to serve as a military parade ground. At times of crisis or
fiesta, it was the space where a large crowd might gather. Like the Italian
piazza, the plaza remains a center of community life that is only equaled by the market-place.

Most colonial cities in
Spanish America and the
Philippines were planned around a square plaza de armas, where troops could be mustered, as the name implies, surrounded by the governor's palace and the main church. A plaza de toros is a
bullring.

In the US, they can be used to open spaces for low income neighborhoods, and can also the overall aesthetic of the surrounding area boosting economic vitality, pedestrian mobility and safety for pedestrians.[2] Most plazas are created out of a collaboration between local non-profit applicants and city officials which requires approval from the city.[3]

In modern usage, a plaza can be any gathering place on a street or between buildings, a street intersection with a statue, etc. Today's metropolitan landscapes often incorporate the "plaza" as a design element, or as an outcome of zoning regulations, building budgetary constraints, and the like. Sociologist
William H. Whyte conducted an extensive study of plazas in
New York City: his study humanized the way modern urban plazas are conceptualized, and helped usher in significant design changes in the making of plazas.

Buildings called 'Plaza'

The first purpose-built shopping center in the United States, opened in
Kansas City, Missouri in 1922, knowingly took the name of "
Country Club Plaza" and adopted Spanish architectural details.[5] More recently plaza has been used to describe a
shopping complex, similar to a
shopping mall, borrowing its connotations of a center of cultural life. The name is currently even applied to a single building with some semi-public street-level areas, often with a hotel or office tower above, while mall more often refers to multiple buildings or a street.